I just found a little bug in HxD's search and replace algorithm. I tried to delete the linebreaks from a textfile with about hundert lines and in each line one ascii char.
I used search&replaxe in hex data mode with "0D 0A" as search phrase and an empty replacement. After running the replacement operation every second occourence of "0D 0A" is left over which is not as it should be (IMHO)...